British Airways (BA) has suspended 15 of its cabin crew for the “intimidation of staff” on Facebook.

The cabin crew workers were said to have made comments on Facebook and sent private e-mails about a “name and shame” list of pilots who had volunteered to work as cabin staff to help break the potential cabin crew strike.

The airline has also demanded that unions reveal the identities of a further 32 members of the cabin crew union Bassa, who posted messages about the list on a thread on its discussion forum, the Guardian has reported.

A BA spokesman confirmed “a number of staff” had been suspended while the airline investigated “allegations of reports of staff being threatened”.

It is thought the wave of suspensions began last weekend after one cabin crew worker obtained a list of 40 pilots who had volunteered to work as cabin crew should a strike be called. That worker posted a message on Facebook saying they had the list, and asking others what they should do with it.

Unite’s assistant general secretary Len McCluskey said: “BA has unleashed a cyberspace witch-hunt. Cabin crew have been suspended simply for being a Facebook friend. This is McCarthyism for the internet age.

“This bears all the hallmarks of a management drunk on its own machismo, regardless of the damage done to the airline’s image and reputation. It is now time for BA’s management to quit harassing its workforce and get back to negotiating a solution to the dispute.”

Letters given to suspended staff said: “You have been suspended because of allegations that, in relation to your activity on Facebook, you took part in conduct likely to harass a BA colleague and/or incited others to take part in such conduct.”

The suspended staff were also told they were being accused of having “committed serious breaches under BA’s data protection policy by accessing and using, or attempting to access and use, personal data of a BA colleague or colleagues for illegitimate and/or unauthorised purposes”.

The suspended crew now face a “preliminary investigation” and could ultimately be dismissed for gross misconduct.